Product details:

Hays Steel Flywheels are manufactured from certified billet material that will not break up under the stress of high RPM and severe punishment of racing. Available in weights up to 50 pounds for specialized applications, most Hays Flywheels are drilled with both the Borg & Beck and Long-Style clutch pattern. Hays flywheels are certified under SFI spec 1.1. Part No. 10-130 is a neutral (zero) balanced flywheel for internal balancing. Application: Chevy 1955-85 All V8 with large bellhousing except 400 & 454. Pressure Plate Pattern: Borg & Beck/Diaphragm 10.5" & Borg & Beck/Long/MK-XII 11", Ring Gear Teeth: 168, Weight: 30.